What is an HttpServletResponse?
All Known Implementing Classes: HttpServletResponseWrapper public abstract interface HttpServletResponse extends ServletResponse. Extends the ServletResponse interface to provide HTTP-specific functionality in sending a response. For example, it has methods to access HTTP headers and cookies.
What is the use of response setHeader in Java?
setHeader. Sets a response header with the given name and value. If the header had already been set, the new value overwrites the previous one. The containsHeader method can be used to test for the presence of a header before setting its value.
What is HttpServletRequest and HttpServletResponse?
The HttpServletRequest object can be used to retrieve incoming HTTP request headers and form data. The HttpServletResponse object can be used to set the HTTP response headers (e.g., content-type) and the response message body.
What is HttpServletResponse in Java?
HttpServletResponse is a predefined interface present in javax. servlet. http package. It can be said that it is a mirror image of request object. The response object is where the servlet can write information about the data it will send back.
What is the difference between setHeader and addHeader methods?
Both setHeader() and addHeader() will add a header and value to the response if the header is not already in the response. The difference between set and add shows up when the header is there. In that case: setHeader() overwrites the existing value, whereas addHeader() adds an additional value.
Which method defined in the HttpServletResponse may be used to set the content type?
The class HttpServletResponse defines the getWriter method. B. setContentType sets the content type of the response being sent to the client.
What is HttpServletRequest in servlet?
HttpServletRequest is an interface and extends the ServletRequest interface. By extending the ServletRequest this interface is able to allow request information for HTTP Servlets. Object of the HttpServletRequest is created by the Servlet container and, then, it is passed to the service method (doGet(), doPost(), etc.)
Which method sets the locale of the response?
setLocale
setLocale. Sets the locale of the response, setting the headers (including the Content-Type’s charset) as appropriate. This method should be called before a call to getWriter() . By default, the response locale is the default locale for the server.
Which method of HttpServletResponse is used?
sendRedirect() method
The sendRedirect() method of HttpServletResponse interface can be used to redirect response to another resource, it may be servlet, jsp or html file. It accepts relative as well as absolute URL.
In which file do we define a Serviet mapping?
Java web applications use a deployment descriptor file to determine how URLs map to servlets, which URLs require authentication, and other information. This file is named web. xml , and resides in the app’s WAR under the WEB-INF/ directory. web.
How HttpServletRequest object is created?
Object of the HttpServletRequest is created by the Servlet container and, then, it is passed to the service method (doGet(), doPost(), etc.) of the Servlet. Extends the ServletRequest interface to provide request information for HTTP servlets.
What is HttpServletRequest in spring?
HttpServletRequest is an interface which exposes getInputStream() method to read the body. By default, the data from this InputStream can be read only once.
What is the use of HttpServletResponse?
public interface HttpServletResponse extends ServletResponse Extends the ServletResponse interface to provide HTTP-specific functionality in sending a response. For example, it has methods to access HTTP headers and cookies.
How to set HTTP response header in a servlet program?
There are following methods which can be used to set HTTP response header in your servlet program. These methods are available with HttpServletResponse object. String encodeRedirectURL(String url) Encodes the specified URL for use in the sendRedirect method or, if encoding is not needed, returns the URL unchanged.
What is the use of set character encoding in http?
Sets the character encoding (MIME charset) of the response being sent to the client, for example, to UTF-8. Sets the length of the content body in the response In HTTP servlets, this method sets the HTTP Content-Length header.
How does the response header get its value from the header?
Gets the value of the response header with the given name. If a response header with the given name exists and contains multiple values, the value that was added first will be returned.